St. Louis County, MO Building Setbacks & Zoning: Structure Height Limits (2026)
Key Facts
- R-1 dwelling height cap
- 3 stories or 45 ft, whichever is less
- R-1 non-dwelling structure cap
- 60 ft above grade
- R-6A dwelling height cap
- 4 stories, basement included
- Accessory building rule
- Never taller than the primary structure
- Extra height route
- Conditional Use Permit, §1003.181
- Further limits near
- Air Navigation Space areas, §1003.161
Summary
Height limits climb with zoning density in unincorporated St. Louis County. The R-1 Residence District caps dwellings at three stories or 45 feet, whichever is less, and non-dwelling structures at 60 feet, while the denser R-6A district allows dwellings up to four stories, including a basement level, before hitting the same 60-foot ceiling on other structures.
6.Height limitations for structures. Other than telecommunication towers the maximum height of structures in the "R-1" Residence District shall be as set out below:(1)No building elevation of any dwelling structure or building accessory to a dwelling structure shall exceed three (3) stories or forty-five (45) feet in height, whichever is less.(2)No accessory building shall be taller than the primary structure.(3)All other structures, other than a local public utility facility authorized by a conditional use permit, shall not exceed sixty (60) feet in height above the average finished ground elevation at the perimeter of such structure; except that the height of structures may be further restricted as provided in section 1003.161 "Air Navigation Space Regulations."
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: Code of Ordinances: Supplement 85 | Traffic: Supplement 80).
Full Breakdown
6 sets the R-1 rule: no dwelling, or building accessory to a dwelling, may exceed three (3) stories or forty-five (45) feet, whichever is less, and no accessory building may be taller than the primary structure it serves. 161 near flight paths. 6, raises the dwelling cap to four (4) stories, expressly counting any basement dwelling space toward that total, while holding non-dwelling structures to the same 60-foot ceiling as R-1. The pattern repeats across the chapter's residence districts: height allowances loosen as a district's permitted density rises, with R-1 the most height-restrictive standard residential zone.
Nursing home developments get their own, separate density-and-height track within each district; in R-1 they are held to the same three-story/45-foot ceiling as ordinary dwellings, while R-6A allows nursing homes up to four stories or 60 feet along with a 25-units-per-acre density cap. 181 before the Planning Commission.
Violations & Fines
A dwelling or accessory building that exceeds its district's story or foot limit, or an accessory building taller than the house it serves, will be denied a building permit and can be flagged for correction mid-construction by the Department of Planning. An applicant seeking extra height for a use not otherwise authorized must obtain a Conditional Use Permit from the Planning Commission, and a denial may be appealed to the Board of Zoning Adjustment.
Frequently Asked Questions
How tall can I build a house in unincorporated St. Louis County?
Can my detached garage be taller than my house?
Are there height limits for non-residential structures in a residential zone?
Sources & Official References
Other rules in St. Louis County
Compare St. Louis County to another location·View the Missouri building setbacks & zoning overview
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